Mobile machines are used to perform a variety of tasks. As an example, in an earthworking environment such as a mining site, mobile machines, e.g., off-road mining trucks, haul material throughout the site.
For repetitive tasks such as above, it is becoming advantageous and desirable to operate the mobile machines autonomously. The environment in which the trucks operate may be harsh, and more efficient operations may be attained if the human fatigue factor is eliminated.
As an example of using off-road mining trucks autonomously, U.S. Pat. No. 5,615,116, issued to Gudat et al., provides an exemplary disclosure of a system for autonomous operations of mobile machines. In this patent, Gudat et al. discloses a fleet of off-road mining trucks operating autonomously at a mining site. Parameters such as position determination, navigation, path planning, and machine control are performed without the aid of human operators.
An important factor in enabling a mobile machine to operate autonomously is the ability to detect obstacles in the machine's path of travel, and to respond in an acceptable manner when obstacles are detected. For example, U.S. Pat. No. 5,612,883, issued to Shaffer et al. teaches a system and method for detecting obstacles in the path of a mobile machine. However, Shaffer et al. does not disclose any method for planning a path around an obstacle when an obstacle is detected. The normal course of action when encountering an obstacle is to stop the mobile machine and notify a fleet manager to remove the obstacle.
In U.S. Pat. No. 5,570,285, Asaka et al. discloses a method and apparatus for planning a route around an obstacle when one is detected. However, in an environment where several mobile machines travel the same paths, each mobile machine that encounters an obstacle must respond individually. More efficient operations would be gained by sharing the information of a first mobile machine to travel around an obstacle with the remainder of the mobile machines.
The present invention is directed to overcoming one or more of the problems as set forth above.